Liquefied gas dispensing system



Jan. 3, 1950 L.. J. WHITE 2,493,708

LIQUEFIED GAS DI SPENSING SYSTEM Filed QG'b. 26, 1938 2 Sheets-Sheet l Jan. 3, 1950 L. J. WHITE LIQUEFIED GAS DISPENSING SYSTEM 2 Sheets-Sheet 2 Filed Oct. 26, 1938 Patented Jan. 3, 1950 LIQUEFIED GAS, DISPENSING @SYSTEM -Lo'yd J White,--Sarr Antonio; Tex., *assignor to 1 Southern? SteelaaGOZ, San Antonio; Tex;, :a' 'corpor'ation of Texas Application (lcltobr, 26, 1938,. SerialNO. 23.7,113

' 4' Claims.

1 This invention-relates to liquefiedgas dispensing systems of the typewhereinliquid petroleum =gas is stored in an underground pressure tank and "is vaporized bytheheat of the surrounding earth "and;- among other objects; aims to provide improved means to generate and-deliver-gas of uniform heatingvalue in systems of the general type disclosed in .U'. 'S.--Pa-tents Reissue 20,624 and No. "251213675. The butane-mixtures commonly "employed in-such' systems contain some more volatile constituents; chiefly -iso-butane and propane.

*"Most orl the 'mixtures contain-from l co-25% propane! Normal butane vapor has a heating value-of approximately 3274 B. t. u.s per cubic foot; while propane .has aboutZBlQ B. t. u.s, both at 60 F. and30 inches mercury column. When a 1:? tank is'fllled,ithegassinitially generatedlcontains a high percentage of propaneavaporzbecause:the propanevaporizes. first, .andtharesulting mixture is not as rich as butane vapor. 'Thus, the gas becomes richer as the supplyin the tank-'is-exhausted,-because the 'liquidin the tank contains a progressively higher-pereentageof butane? This necessitates adjustmentsofthef-air supply to the burners of consuming appliances to insure I complete' combustion -Therefore'ithe principalcobject of this invention isvtor-provide a secondary vaporizing chamber to which the liquefied gas is delivered at a reducedpressure fromthebot- "tom-portion of'the" tank, whereby to "insure the delivery of gas of substantially uniform B. t. u. content and avoid the necessity of adjusting burners to vary the supply of air every time the tank is refilled.

Other aims and advantages of the invention will appear in the specification, when considered in connection with the accompanying drawings, wherein:

Fig. 1 is a sectional view, partly in elevation, showing a system embodying the invention;

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a top plan view, on an enlarged scale, of a combination fitting shown in Fig. 1; and

Fig. 4 is a sectional view taken on the line 44 of Fig. 3.

Referring particularly to the drawings, the type of system there shown for illustrative purposes is similar in many respects to that disclosed and claimed in the aforesaid Patent No. 2,121,675. However, it is to be understood that the present invention is applicable to other types of systems, such, for example, as is shown in the aforesaid reissue patent or in Patent No. 2,121,673. In this instance, there is shown an underground pressure 2 storage tank" l-n havingastandpipe l|-to-which is connected a-co'mbination' fitting l2 carrying'a filling valve 13; vapor =return'va-lve l 4; safety '--re- "lief valve l5ppressure'gauge l6-a-nd"a=leve1 gauge -l! adapted to'be opera'ted -by a fioat l8, all'exactly as disclosed in said PatentNo'." 2&1213675. These parts-andother "dispensing appurtenances are housed within' a casing' l9 'simi-larto-"that shown in-Reissue- Pa-terrt"",624.

l0 Instead of"dispens inggenerated gas through "the standpipeandthe combination-fitting I2-;-as disclosed in Patent 2,121,675;-the -liquefiedgas is delivered from the bottom-portion of'thetank to a vap r generating chamber or ccmpartment 20 l 5 --prefera-bly' arranged "within-the tank and-shown as having a-bottompo'rtion 2Iinthe-form of a semi-circular invertedtrough welded to the bot- -tom of the tankto provide additional heat 2 exchanging "surface; *Imcold' climates; the'pipe 20 20 may be'closed at'its-iowerend andexten'd-through the tank-bottom 'intothe-fground well below the frost line, where it"=wil1 absorb more vaporizing heat from the earth.'-"-The main "part of this -chambermay be and preferably is composed of a large piece of pipe welded" at-itsupper "e'ndto the upper wall-or'topof the-tank.- Liquefied-gas is delivered to it--from the-bottom portion of the -tankthrough" an eduction-pipe 22 "extending throughthtop-of the tank, aspressure'reducing valve 23" irr'tlrecasing-Fl B and apipe 24 leading -back=- through the tankwvall intothe upper p0rtion of said chamber, both pipes preferably being welded in the tank wall. The pressure reducing valve is vented to the atmosphere by a pipe 25 35 leading to the upper part of the casing. The pressure reducing valve lowers the pressure of the fuel within the vaporizing chamber and insures its vaporization by absorption of heat from the contents of the tank, the vaporizing temperature of the fuel at the lower pressure being less than that in the tank. The pressure is reduced to, say, five or ten pounds, gage. Incidentally, the tank pressure ranges from 40 to 50 pounds, depending upon the particular mixture of gas used and the temperature of the tank. The liquefied gas immediately vaporizes in the chamber and the pressure is kept substantially constant.

The gas is delivered from the chamber 20 through a discharge pipe 26 preferably welded in the top wall of the tank and this pipe is shown as having an elbow 21 at its upper end connected to a valve casing 28 carrying a manually operable cut-off valve 29, a branch or service nipple 3i! and an excess flow check valve 3|. The valve casing is shown as being integral with the comsure reducing regulator 33 to the outlet branch or service nipple 30. The regulator has the usual vent pipe 34 extending to the upper portion of the casing l 9. A service pipe 35 leads downwardly from the regulator to the bottom of the casing and outwardly through the casing wall, adjacent to the top of the tank.

From the foregoing description, it will be seen that the improved system is very simple in its design and easy to assemble. The vaporizer chamber'insures a constant supply of dry gas of substantially uniform richness. The gas pressure in the tank serves to force the liquefied gas as it is needed through the reducing valve and the fiowwill stop when the pressures are balanced against each other.

Obviously, the present invention is not restricted to the particular embodiment thereof herein shown and described. Moreover, it is not indispensable that all the-features of the invention be used conjointly, since they may be em- ;ployedadvantageously in various combinations and sub-combinations. What is claimed is: 1. In a gas dispensing system of the character described having a storage tank, a separate vaporizing chamber within the tank comprising a pipe having an inverted trough-shaped bottom portion weldedin the tank; a liquid eduction pipe leading from the bottom portion of said tank into said vaporizing chamber; a pressure reducing valve connected between said eduction pipe and said chamber outside the tank; a discharge pipe connected to said vaporizing chamber to deliver the gas to a service pipe; and filling valves and gauges connected to the tank.

2. In a gas dispensing system of the class described, an undergroundpressure storage tank in heat exchanging relation with the surrounding earth; a vaporizing chamber within the tank; a

liquid eduction pipe leading from the bottom por- 4 tion of the tank through the tank wall and into the vaporizing chamber; a pressure reducing valve connected to said eduction pipe outside the tank; a gas discharge pipe leading from said vaporizing chamber; control appurtenances connecting said discharge pipe to a service pipe; a protecting casing for said pressure reducing valve and control appurtenances; and a vent for the pressure reducing valve in said casing.

' 3. In a liquefied petroleum gas dispensing system of the class described, a pressure storage tank adapted to be buried in the ground in heat exchanging relation with the surrounding earth; a liquid eduction pipe leading from the bottom portion of the tank through the tank wall to discharge liquid due to the vapor pressure in the tank; a vaporizing chamber connected to the liquid eduction pipe having a wall constituting a portion of the tank and adapted to absorb heat directly from the earth; a pressure reducing regulator having a valve in said liquid eduction pipe outside of said tank adapted to discharge a mixture of liquid and vapor into said vaporizing chamber; a vapor discharge pipe connected to said vaporizing chamber, and a filling valve connected to the tank. 7

4. A liquefied petroleum gas dispensing system, as set forth in claim 3, wherein a second pressure reducing valve is connected to said vapor discharge pipe; and said vaporizing chamber is located within the confines of the tank and partially submerged within the liquid contained therein to absorb some vaporizing heat therefrom.

LOYD J. WHITE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,752,165 Ford Mar. 25, 1930 1,752,166 Ford Mar. 25, 1930 r 1,935,925 Wannack 1 Nov. 21, 1933 2,121,675 White Oct. 18, 1937 2,155,340 Stl'Olld .Apr..18, 1939 V FOREIGN PATENTS Number Country Date Germany Mar. 14, 1931 

